Elastic gloves each entirely unitarily made of rubber or resin are widely used at homes, in plants and in medical facilities to protect skin of human hands, to prevent food poisoning and infectious diseases and/or to protect objects to be handled (e.g., semiconductor devices and precision instruments) from sebum of human hands. It is noted that not only gloves made of rubber but also gloves made of resin are generally referred to as “elastic gloves” and, therefore, these gloves are collectively referred to as “elastic gloves” in the present invention regardless of whether the gloves are made of rubber or resin.
One of known types of elastic gloves is such that the generally entire interior surface of the elastic glove (ranging from a fingertip portion to a cuff portion of the elastic glove) is flocked with a multiplicity of short-fibers (piles) such as of cotton or rayon to facilitate attachment and detachment of the elastic glove to/from a hand and to improve the texture of the interior surface when the glove is worn on the hand.
The elastic glove is generally produced by a so-called dipping method.
For production of an elastic glove entirely unitarily made of rubber and having an interior surface flocked with piles, for example, an unvulcanized or prevulcanized liquid latex composition is first prepared by blending various additives such as a vulcanizing agent to a rubber latex. Further, a ceramic mold conformal to the three-dimensional shape of the elastic glove is prepared, and its surface is treated with a coagulant (mainly a calcium nitrate aqueous solution).
Subsequently, the mold is held with its fingertip side down and with its cuff side up, and dipped, its fingertip side first, into the latex composition. Then, the mold is taken out, its cuff side first, from the latex composition. Thus, the latex composition adheres to the surface of the mold to form a latex composition film.
In turn, piles are deposited on the film by either or both of a spraying process or an electrostatic deposition process, and then the film is heated together with the mold for drying the latex composition and vulcanizing the rubber. Alternatively, the film is first dried, and then heated together with the mold for the vulcanization of the rubber.
Thus, portions of the individual piles adhering to the film are embedded in the vulcanized film to be fixed to the film, and remaining portions of the individual piles are exposed from the film. That is, the piles are flocked on a surface of the film later serving as the interior surface of the glove.
Thereafter, the elastic glove is turned inside out to be demolded or, alternatively, the elastic glove is demolded and then turned inside out, so that the surface of the film flocked with the piles defines the interior surface of the elastic glove. Thus, the elastic glove is produced, which is entirely unitarily made of the rubber and has the interior surface flocked with the piles.
The elastic glove may have a double layer structure including an outer layer defining an exterior surface thereof and an inner layer defining the interior surface thereof flocked with the piles.
The elastic glove of the double layer structure is produced by dipping a mold into a latex composition as a material for the outer layer, taking out the mold to form a film, dipping the resulting mold into a latex composition as a material for the inner layer to form a film, depositing piles on a surface of the film, and entirely vulcanizing the rubber in the films (see, for example, Patent Document 1).
An elastic glove entirely and unitarily made of a resin is produced in substantially the same manner as described above, except that a latex composition prepared by blending various additives in a resin emulsion is used instead of the latex composition containing the rubber latex. In strict sense, the composition containing the resin emulsion is not a latex composition. However, the composition containing the resin emulsion as well as the latex composition containing the rubber latex are herein referred to as “latex composition” for convenience.
It is known that, in the dipping process, the amount of the latex composition adhering to the mold surface, i.e., the thickness of the film, is increased as the period during which the mold is dipped in the latex composition is increased.
Therefore, where the mold is dipped, its fingertip side first, in the latex composition and then taken out, its cuff side first, from the latex composition as described above, the fingertip side of the mold is dipped in the latex composition for a longer period of time than the cuff side of the mold. Thus, the latex composition is liable to adhere in a greater amount on the fingertip side than on the cuff side, so that the thickness of the film tends to be greater on the fingertip side than on the cuff side.
Further, the drying speed of the latex composition tends to be increased as the thickness of the film is reduced. Conversely, the drying speed of the latex composition tends to be reduced as the thickness of the film is increased.
Particularly, where the films of the latex compositions are stacked one on the other for the production of the elastic glove of the double layer structure, these tendencies are enhanced.
Therefore, even if the piles are substantially simultaneously deposited uniformly over the entire surface of the film of the latex composition formed on the generally entire surface of the mold, the individual piles are liable to be embedded in the film in different pile embedded states on the fingertip side and on the cuff side.
That is, if the period required to dry the film is increased, the individual piles deposited on the film tend to be embedded to a greater extent in the film.
Accordingly, a greater number of piles are embedded to a greater extent in the film on the fingertip side where the film has a greater thickness and hence is more slowly dried.
On the fingertip side, therefore, the piles which are harder than the rubber and the resin are embedded to a greater extent in the film. This reduces the flexibility of the film, and gives a rough touch on the interior surface of the elastic glove, deteriorating the texture of the interior surface of the elastic glove.
On the cuff side where the film has a smaller thickness and hence is quickly dried, on the other hand, the piles are embedded to a smaller extent in the film, so that a greater number of piles are liable to fall out of the vulcanized film.
Therefore, the number of piles falling out of the film is increased on the cuff side. This reduces the effect of facilitating the attachment and the detachment of the elastic glove to/from the hand and improving the texture of the interior surface of the elastic glove by the pile flocking.